<svg xmlns:svg="http://www.w3.org/2000/svg">
  <svg:marker
    markerUnits="strokeWidth"
    viewBox="0 0 10 10"
  />
  <svg:marker
    markerUnits="<error descr="Wrong attribute value">strokeWidt</error>"
  />
  <marker markerUnits="strokeWidth"
          viewBox="0 0 10 10"/>
  <pattern patternContentUnits="userSpaceOnUse"
           patternUnits="userSpaceOnUse"/>
</svg>
<svg:pattern
  xmlns:svg="http://www.w3.org/2000/svg"
  patternContentUnits="userSpaceOnUse"
  patternUnits="userSpaceOnUse"
/>
<svg:pattern
  xmlns:svg="http://www.w3.org/2000/svg"
  patternContentUnits="<error descr="Wrong attribute value">userSpaceOnUsed</error>"
/>
